The COVID-19 pandemic caused by the novel coronavirus SARS-CoV-2 has caused an unprecedented global crisis, and a proliferation of conspiracy theories. These conspiratorial beliefs has contributed to weakening the credibility of government public health measures, limiting citizens' access to reliable sources of information, and disrupting the response of health systems to the crisis. Several hypotheses have been proposed in psychology and social science to understand the genesis of these beliefs during a pandemic, including generational, socio-cultural and political characteristics of individuals, and psychological factors such as the desire to preserve one's safety, to maintain a positive self-image, or even to strengthen its social role. However, recent discoveries in cognitive science about belief updating mechanisms offer new insights into the generation of conspiratorial beliefs across time and culture. In this paper, we offer a definition of conspiracy theory and a classification of conspiracy beliefs during the COVID-19 pandemic. We show how the mechanisms of belief updating may explain the genesis of conspiracy theories, and we propose several hypotheses supported by contemporary research in cognitive and social science.
